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The 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has become a standard procedure for the diagnosis, staging, and restaging in lymphoma patients. However, a relative high rate of false-positive results has been reported. We report a case of a 40-year-old man with a previous history of a nodal follicular lymphoma, stage IVA, treated with R-CHOP, which showed strong 18F-FDG uptake in the Waldeyer’s tonsillar ring during his follow-up, being considered highly suspicious of relapsed lymphoma. A surgical removal of the palatine tonsils and adenoids was performed, which showed reactive follicular hyperplasia. Furthermore, bone marrow biopsy revealed absence of neoplasia. The patient is still in follow-up with no signs of recurrent lymphoma. This case illustrates that, despite the high sensitivity for the detection of recurrent lymphoma, 18F-FDG uptake should be interpreted with great caution and confirmatory studies should be performed before any therapy.  相似文献   
64.
Aggregatibacter actinomycetemcomitans is a Gram‐negative bacteria highly associated with localized aggressive periodontitis. The recognition of microbial factors, such as lipopolysaccharide from A. actinomycetemcomitans (AaLPS), in the oral environment is made mainly by surface receptors known as Toll‐like receptors (TLR). TLR4 is the major LPS receptor. This interaction leads to the production of inflammatory cytokines by myeloid differentiation primary‐response protein 88 (MyD88) ‐dependent and ‐independent pathways, which may involve the adaptor Toll/interleukin‐1 receptor‐domain‐containing adaptor inducing interferon‐β (TRIF). The aim of this study was to assess the involvement of MyD88 in alveolar bone loss induced by AaLPS in mice. C57BL6/J wild‐type (WT) mice, MyD88, TRIF or TRIF/MyD88 knockout mice received 10 injections of AaLPS strain FDC Y4 (5 μg in 3 μl), in the palatal gingival tissue of the right first molar, every 48 h. Phosphate‐buffered saline was injected in the opposite side and used as control. Animals were sacrificed 24 h after the 10th injection and the maxillae were removed for macroscopic and biochemical analyses. The injections of AaLPS induced significant alveolar bone loss in WT mice. In the absence of MyD88 or TRIF/MyD88 no bone loss induced by AaLPS was observed. In contrast, responses in TRIF?/? mice were similar to those in WT mice. Diminished bone loss in the absence of MyD88 was associated with fewer TRAP‐positive cells and increased expression of osteoblast markers, RUNX2 and osteopontin. There was also reduced tumor necrosis factor‐α production in MyD88?/? mice. There was less osteoclast differentiation of hematopoietic bone marrow cells from MyD88?/? mice after AaLPS stimulation. Hence, the signaling through MyD88 is pivotal for AaLPS‐induced osteoclast formation and alveolar bone loss.  相似文献   
65.
Although long known and the most prevalent movement disorder, pathophysiology of essential tremor (ET) remains controversial. The most accepted hypothesis is that it is caused by a dysfunction of the olivocerebellar system. Vilela Filho et al. [2001; Stereotact Funct Neurosurg 77:149–150], however, reported a patient with unilateral hand ET that was completely relieved after a stroke restricted to the contralateral posterior putamen and suggested that ET could be the clinical manifestation of posterior putamen hyperactivity. The present study was designed to evaluate this hypothesis in the most often used model of ET, harmaline‐induced tremor in rats. Fifty‐four male Wistar rats were randomly distributed into three groups: experimental (EG), surgical control (SCG), and pharmacological control (PCG) groups. EG animals underwent stereotactic unilateral posterior striatotomy. SCG rats underwent sham lesion at the same target. PCG served exclusively as controls for harmaline effects. All animals received, postoperatively, intraperitoneal harmaline, and the induced tremor was video‐recorded for later evaluation by a blind observer. Thirteen animals were excluded from the study. Limb tremor was reduced ipsilaterally to the operation in 20 of 21 rats of EG and in two of nine of SCG, being asymmetric in one of 10 of PCG rats. Comparisons between EG × SCG and EG × PCG were statistically significant, but not between SCG × PCG. Limb tremor reduction was greater in anterior than in posterior paws. Lateral lesions yielded better results than medial lesions. These results suggest that the posterior striatum is involved with harmaline‐induced tremor in rats and support the hypothesis presented. © 2013 Wiley Periodicals, Inc.  相似文献   
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The objective of this study was to evaluate the influence of resin-based restorations on the interpretation of digital and conventional radiographic images and to correlate the proposed diagnosis with decision-making. Class II cavities were prepared in one of the proximal surfaces of extracted human molars. Teeth were divided into five groups (n = 10) according to the restoratives used: Natural Flow (NF) and Filtek Supreme (FS); Filtek Flow (FF) and FS; Tetric Flow (TF) and FS; Protect Liner F (PLF) and FS; and FS alone. Bitewing radiographs were taken using conventional and digital systems. Subjective analysis was performed for each surface: no restoration; restored teeth; or restored teeth with gap. Based on the given diagnosis, clinical conduct was then indicated. Material radiopacity was determined according to ISO 4049. A Fisher exact test evaluated the influence of the restoratives on the diagnosis. Means were compared using ANOVA and the Games-Howell test. A Friedman test was used to analyze the influence of the systems on the diagnosis, and a binomial test was used to analyze the association between the presence of gaps and the decision to replace the restoration (P = 0.05). For each system, TF+FS was significantly associated with a high percentage of correct diagnoses. The opposite was the case for PLF+FS, which differed from all other groups. Radiographic systems presented similar behaviors, except for NF+FS. Apart from PLF, adequate radiopacity was observed. Diagnosis was influenced by restorative materials, regardless of the radiographic system used. The low radiopacity of PLF led to a greater number of erroneous diagnoses. Moreover, the decision-making process was influenced strongly by the given diagnosis.  相似文献   
68.
Soft tissue infections are characterized by acute inflammation, diffuse edema, and suppuration, and are often associated with symptoms such as malaise, fever, tachycardia, and chills. Necrotizing fasciitis is a destructive bacterial infection affecting subcutaneous tissue and superficial fascia and is associated with high rates of mortality. It usually involves the abdomen and extremities, but it also can occur in the head and neck. Early diagnosis is critical and the most commonly accepted treatment includes radical surgical intervention and administration of broad-spectrum antibiotics. This article reports and discusses the case of a patient with odontogenic cervicofacial necrotizing fasciitis, and emphasizes the importance of early and effective treatment.  相似文献   
69.
Worldwide, there are up to 900 million people over 60 years old, of which more than half are physically inactive. Low physical fitness seems to be the major risk factor for cardiovascular diseases and mortality in this population. Alternative methods of exercise, such as martial arts, may be an option to improve physical fitness in the elderly. This study aimed to verify the effects of Brazilian jiu-jitsu (BJJ) training on the functional fitness of elderly men. Sixty-two elderly men were divided in two groups (experimental and control). The experimental group was submitted to a 12-week intervention of BJJ (2 times week?1; 90-min session?1). Physical fitness tests and anthropometric measurements were performed before and after intervention in both groups. No statistical differences were found between groups before and after the intervention. The experimental group improved in all performed physical fitness tests. Effect size showed that intervention had a small effect on upper body flexibility; a moderate effect for upper body strength, lower body flexibility, and motor agility/dynamic balance; and a large effect on lower body strength and aerobic endurance. BJJ seems to improve functional fitness in elderly men and may be an alternative method to enhance this population’s health and quality of life.  相似文献   
70.
The last decade has revealed an unexpected fungal diversity associated with natural rocks, often collected in environments influenced by harsh climatic conditions. Yet the phylogenetic affiliations and the taxonomy of many of these extreme fungi, mainly within Dothideomycetes, the largest class of Ascomycota, have only partially been described. In the present study we confirm that most rock inhabiting-fungi (RIF) are highly polyphyletic among Dothideomycetidae, mainly within the order Capnodiales, an order otherwise incorporating several families of major plant pathological importance. Novel taxa were identified within the two major and distinct clades of Teratosphaeriaceae, both comprising meristematic black fungi. Thirty one novel species and 13 new genera are proposed, based on ITS and partial nucLSU, RPB2 and BT2 sequences.  相似文献   
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